Digital audio broadcasting modem interface system for receiving multi-channel and its working method

Abstract

Disclosed is a DAB (Digital Audio Broadcasting) modem interface for receiving multi-channel, which is capable of receiving two channels at once by providing a sub-channel filtering function to the DAB modem interface, and a method of operating the same. The DAB modem interface includes a serial interface for capturing channel data in bit stream data output from the DAB modem, buffer switching means for classifying the channel data captured by the serial interface for each channel and storing the classified channel data in two buffers assigned for each channel, and sub-channel filtering means for performing a sub-channel filtering operation of comparing a channel value acquired from the multimedia processor with a sub-channel ID value acquired in the course of capturing of the channel data, and generating control signals for controlling the serial interface to provide information on two channels to be captured and the buffer switching means to store data into the two buffers.

1 . A DAB (Digital Audio Broadcasting) modem interface for receiving a multi-channel, the DAB modem interface interfacing between a DAB modem and a multimedia processor in a DMB (Digital Multimedia Broadcasting) system, comprising: 
 a serial interface for capturing channel data in bit stream data output from the DAB modem;    buffer switching means for classifying the channel data captured by the serial interface for each channel and storing the classified channel data in two buffers assigned for each channel; and    sub-channel filtering means for performing a sub-channel filtering operation of comparing a channel value acquired from the multimedia processor with a sub-channel ID value acquired in the course of capturing of the channel data, and generating control signals for controlling the serial interface to provide information on two channels to be captured and the buffer switching means to store data into the two buffers.    
   
   
       2 . The DAB modem interface according to  claim 1 , wherein the control signals are generated by comparing the channel value acquired from the multimedia processor with a sub-channel ID value acquired through a separate sub-channel ID port.  
   
   
       3 . The DAB modem interface according to  claim 1 , wherein the control signals are generated when the channel value acquired from the multimedia processor is equal to the sub-channel ID value acquired in the course of capturing of the channel data.  
   
   
       4 . The DAB modem interface according to  claim 1 , wherein the buffer switching means has a double buffer structure for assigning buffers separately according to a channel classification in order to store data for each channel.  
   
   
       5 . The DAB modem interface according to  claim 1 , wherein the buffer switching means comprises: 
 a CH 0 _CH 1  switching block for determining whether the channel data input based on the control signals correspond to which of a sub-channel  0  and a sub-channel  1 ;    a BUF 0 _BUF 1  switching block for determining whether the channel data corresponding to the sub-channel  0  and the sub-channel  1  determined by the CH 0 _CH 1  switching block are stored in which of BUF 0  and BUF 1 , which are the two buffers assigned for each channel; and    a FIFO control block for determining whether the data processed in the BUF 0 _BUF 1  switching block are loaded in the buffers or are read by the multimedia processor based on buffer control signals generated by the BUF_BUF 1  switching block and buffer control signals transmitted from the multimedia processor via an APB (Advanced Peripheral Bus).    
   
   
       6 . The DAB modem interface according to  claim 5 , wherein the buffer control signals, generated by the BUF 0 _BUF 1  switching block, are signals for data writing operation and the buffer control signals transmitted from the multimedia processor to the FIFO control block via the APB are signals for data reading operation.  
   
   
       7 . The DAB modem interface according to  claim 5 , wherein the BUF 0 _BUF 1  switching block controls such that, when the buffer data writing operation for one of the BUF 0  and the BUF 1 , which are the two buffers assigned for each channel, is completed, the buffer data writing operation for the other of the BUF 0  and the BUF 1  is performed.  
   
   
       8 . A method of operating a DAB modem interface for receiving a multi-channel, comprising the steps of: 
 performing a sub-channel filtering operation for determining whether a sub-channel value of a received transport stream is equal to a sub-channel  0  or a sub-channel  1  set by a user through a CPU;    if the sub-channel value of the received transport stream is equal to the sub-channel  0  or the sub-channel  1  set by the user, by a CH 0 _CH 1  switching block, determining whether the sub-channel value of the received transport stream corresponds to which of the sub-channels  0  and  1  and providing a buffer control signal and values of a buffer address and buffer data of a corresponding channel to the BUF 0 _BUF 1  switching block;    by the BUF 0 _BUF 1  switching block, determining whether data of the channel are stored in which of BUF 0  and BUF 1  (BUF 0 /BUF 1  of channel  0  and BUF 0 /BUF 1  of channel  1 ), which are two buffers assigned for each channel; and    by a FIFO control block, determining whether the data processed in the BUF 0 _BUF 1  switching block are loaded in the buffers or are read by a multimedia processor based on buffer control signals generated by the BUF_BUF 1  switching block and buffer control signals transmitted from the multimedia processor via an APB.    
   
   
       9 . A DAB modem interface system for receiving a multi-channel, wherein data exchange between the DAB modem interface system and a multimedia processor at a decoder stage is implemented through a bus interface, and information on completion of a buffer data writing operation for one buffer of a double buffer for each channel is provided from the DAB modem interface system to the multimedia processor through an interrupt signal.  
   
   
       10 . The DAB modem interface according to  claim 2 , wherein the control signals are generated when the channel value acquired from the multimedia processor is equal to the sub-channel ID value acquired in the course of capturing of the channel data.